Eigen: switch to imported modules and NO_MODULE (#5613)

* Eigen: switch to imported modules and NO_MODULE

Use Eigens native cmake support to replace the custom FindEigen.cmake

* Use target Eigen3::Eigen

* Remove usage of Eigen3_INCLUDE_DIR

* Print Eigens target properties

* Temp: Hard code property list

* Link Eigen to cuda_io

* Revert "Temp: Hard code property list"

This reverts commit 10ded79.

* Revert "Print Eigens target properties"

This reverts commit 93a7b93.

* Link common to cuda_io

* Link common to cuda_features

* Link common to cuda_segmentation

* Link common to gpu_containers

* Fix target name in PCLConfig.cmake.in

* Make all in one installer independent of Eigen3 internals

* Fix cmake errors

* Append existing target_link_libraries

CMakeLists.txt

@@ -318,9 +318,8 @@ endif()
 # Threads (required)
 find_package(Threads REQUIRED)
 
-# Eigen (required)
-find_package(Eigen 3.3 REQUIRED)
-include_directories(SYSTEM ${EIGEN_INCLUDE_DIRS})
+# Eigen3 (required)
+find_package(Eigen3 3.3 REQUIRED NO_MODULE)
 
 # FLANN (required)
 find_package(FLANN 1.9.1 REQUIRED)

PCLConfig.cmake.in

@@ -112,14 +112,11 @@ macro(find_boost)
   endif()
 endmacro()
 
-#remove this as soon as eigen is shipped with FindEigen.cmake
-macro(find_eigen)
+macro(find_eigen3)
   if(PCL_ALL_IN_ONE_INSTALLER)
-    set(EIGEN_ROOT "${PCL_ROOT}/3rdParty/Eigen")
-  elseif(NOT EIGEN_ROOT)
-    get_filename_component(EIGEN_ROOT "@EIGEN_INCLUDE_DIRS@" ABSOLUTE)
+    set(Eigen3_DIR "${PCL_ROOT}/3rdParty/Eigen3/share/eigen3/cmake/")
   endif()
-  find_package(Eigen 3.3)
+  find_package(Eigen3 3.3 REQUIRED NO_MODULE)
 endmacro()
 
 #remove this as soon as qhull is shipped with FindQhull.cmake
@@ -271,8 +268,8 @@ endmacro()
 function(find_external_library _component _lib _is_optional)
   if("${_lib}" STREQUAL "boost")
     find_boost()
-  elseif("${_lib}" STREQUAL "eigen")
-    find_eigen()
+  elseif("${_lib}" STREQUAL "eigen3")
+    find_eigen3()
   elseif("${_lib}" STREQUAL "flann")
     find_flann()
   elseif("${_lib}" STREQUAL "qhull")

cmake/pcl_all_in_one_installer.cmake

@@ -10,7 +10,6 @@ endif()
 # get root directory of each dependency libraries to be copied to PCL/3rdParty
 get_filename_component(BOOST_ROOT "${Boost_INCLUDE_DIR}" PATH)  # ../Boost/include/boost-x_x/ -> ../Boost/include/
 get_filename_component(BOOST_ROOT "${BOOST_ROOT}" PATH)         # ../Boost/include/           -> ../Boost/
-get_filename_component(EIGEN_ROOT "${EIGEN_INCLUDE_DIRS}" PATH) # ../Eigen3/include/          -> ../Eigen3/
 get_filename_component(QHULL_ROOT "${Qhull_DIR}" PATH)          # ../qhull/lib/cmake/Qhull/   -> ../qhull/lib/cmake
 get_filename_component(QHULL_ROOT "${QHULL_ROOT}" PATH)         # ../qhull/lib/cmake/         -> ../qhull/lib/
 get_filename_component(QHULL_ROOT "${QHULL_ROOT}" PATH)         # ../qhull/lib/               -> ../qhull/
@@ -19,7 +18,7 @@ get_filename_component(VTK_ROOT "${VTK_ROOT}" PATH)             # ../VTK/lib/cma
 get_filename_component(VTK_ROOT "${VTK_ROOT}" PATH)             # ../VTK/lib/                 -> ../VTK/
 
 set(PCL_3RDPARTY_COMPONENTS)
-foreach(dep Eigen Boost Qhull FLANN VTK)
+foreach(dep Boost Qhull FLANN VTK)
   string(TOUPPER ${dep} DEP)
   install(
     DIRECTORY "${${DEP}_ROOT}/"
@@ -30,6 +29,57 @@ foreach(dep Eigen Boost Qhull FLANN VTK)
   list(APPEND PCL_3RDPARTY_COMPONENTS ${dep})
 endforeach()
 
+# Try to set EIGEN3_INCLUDE_DIR in case it is
+# no longer exported by Eigen3 itself.
+if (NOT EXISTS ${EIGEN3_INCLUDE_DIR})
+  if (EXISTS ${EIGEN3_INCLUDE_DIRS})
+    set(EIGEN3_INCLUDE_DIR ${EIGEN3_INCLUDE_DIRS})
+  else()
+    set(EIGEN3_INCLUDE_DIR "${Eigen3_DIR}/../../../include/eigen3/")
+  endif()
+endif()
+if(NOT EXISTS ${EIGEN3_INCLUDE_DIR})
+  message(FATAL_ERROR "EIGEN3_INCLUDE_DIR is not existing: ${EIGEN3_INCLUDE_DIR}")
+endif()
+
+# Try to find EIGEN3_COMMON_ROOT_PATH, which is meant to hold
+# the first common root folder of Eigen3_DIR and EIGEN3_INCLUDE_DIR.
+# E.g. Eigen3_DIR              = /usr/local/share/eigen3/cmake/
+#      EIGEN3_INCLUDE_DIR      = /usr/local/include/eigen3/
+#   => EIGEN3_COMMON_ROOT_PATH = /usr/local/
+file(TO_CMAKE_PATH ${Eigen3_DIR} Eigen3_DIR)
+file(TO_CMAKE_PATH ${EIGEN3_INCLUDE_DIR} EIGEN3_INCLUDE_DIR)
+set(EIGEN3_INCLUDE_PATH_LOOP ${EIGEN3_INCLUDE_DIR})
+set(PREVIOUS_EIGEN3_INCLUDE_PATH_LOOP "INVALID")
+while (NOT ${PREVIOUS_EIGEN3_INCLUDE_PATH_LOOP} STREQUAL ${EIGEN3_INCLUDE_PATH_LOOP})
+  if (${Eigen3_DIR} MATCHES ${EIGEN3_INCLUDE_PATH_LOOP})
+    set(EIGEN3_COMMON_ROOT_PATH ${EIGEN3_INCLUDE_PATH_LOOP})
+    break()
+  endif()
+  set(PREVIOUS_EIGEN3_INCLUDE_PATH_LOOP ${EIGEN3_INCLUDE_PATH_LOOP})
+  get_filename_component(EIGEN3_INCLUDE_PATH_LOOP ${EIGEN3_INCLUDE_PATH_LOOP} DIRECTORY)
+endwhile()
+if(NOT EXISTS ${EIGEN3_COMMON_ROOT_PATH})
+  message(FATAL_ERROR "Could not copy Eigen3.")
+endif()
+
+# Install Eigen3 to 3rdParty directory
+string(LENGTH ${EIGEN3_COMMON_ROOT_PATH} LENGTH_OF_EIGEN3_COMMON_ROOT_PATH)
+string(SUBSTRING ${Eigen3_DIR} ${LENGTH_OF_EIGEN3_COMMON_ROOT_PATH} -1 DESTINATION_EIGEN3_DIR)
+string(SUBSTRING ${EIGEN3_INCLUDE_DIR} ${LENGTH_OF_EIGEN3_COMMON_ROOT_PATH} -1 DESTINATION_EIGEN3_INCLUDE_DIR)
+set(dep_Eigen3 Eigen3)
+install(
+  DIRECTORY "${Eigen3_DIR}/"
+  DESTINATION 3rdParty/${dep_Eigen3}${DESTINATION_EIGEN3_DIR}
+  COMPONENT ${dep_Eigen3}
+)
+install(
+  DIRECTORY "${EIGEN3_INCLUDE_DIR}/"
+  DESTINATION 3rdParty/${dep_Eigen3}${DESTINATION_EIGEN3_INCLUDE_DIR}
+  COMPONENT ${dep_Eigen3}
+)
+list(APPEND PCL_3RDPARTY_COMPONENTS ${dep_Eigen3})
+
 if(WITH_RSSDK2)
   get_filename_component(RSSDK2_ROOT "${RSSDK2_INCLUDE_DIRS}" PATH)
   install(

common/CMakeLists.txt

@@ -4,7 +4,7 @@ set(SUBSYS_DEPS)
 
 set(build TRUE)
 PCL_SUBSYS_OPTION(build "${SUBSYS_NAME}" "${SUBSYS_DESC}" ON)
-PCL_SUBSYS_DEPEND(build NAME ${SUBSYS_NAME} DEPS ${SUBSYS_DEPS} EXT_DEPS eigen boost)
+PCL_SUBSYS_DEPEND(build NAME ${SUBSYS_NAME} DEPS ${SUBSYS_DEPS} EXT_DEPS eigen3 boost)
 
 PCL_ADD_DOC("${SUBSYS_NAME}")
 
@@ -179,7 +179,7 @@ target_include_directories(${LIB_NAME} PUBLIC
   $<INSTALL_INTERFACE:include> 
 )
 
-target_link_libraries(${LIB_NAME} Boost::boost)
+target_link_libraries(${LIB_NAME} Boost::boost Eigen3::Eigen)
 
 if(MSVC AND NOT (MSVC_VERSION LESS 1915))
   # MSVC resolved a byte alignment issue in compiler version 15.9

cuda/features/CMakeLists.txt

@@ -26,6 +26,7 @@ set(incs
 set(LIB_NAME "pcl_${SUBSYS_NAME}")
 include_directories("${CMAKE_CURRENT_SOURCE_DIR}/include")
 PCL_CUDA_ADD_LIBRARY(${LIB_NAME} COMPONENT ${SUBSYS_NAME} SOURCES ${srcs} ${incs})
+target_link_libraries(${LIB_NAME} pcl_common)
 
 set(EXT_DEPS "")
 #set(EXT_DEPS CUDA)

cuda/io/CMakeLists.txt

@@ -37,6 +37,7 @@ set(incs
 set(LIB_NAME "pcl_${SUBSYS_NAME}")
 include_directories("${CMAKE_CURRENT_SOURCE_DIR}/include")
 PCL_CUDA_ADD_LIBRARY(${LIB_NAME} COMPONENT ${SUBSYS_NAME} SOURCES ${srcs} ${incs})
+target_link_libraries(${LIB_NAME} pcl_common)
 
 PCL_MAKE_PKGCONFIG(${LIB_NAME} COMPONENT ${SUBSYS_NAME} DESC ${SUBSYS_DESC} PCL_DEPS ${SUBSYS_DEPS} EXT_DEPS ${SUBSYS_EXT_DEPS})
 

cuda/segmentation/CMakeLists.txt

@@ -27,6 +27,7 @@ set(srcs
 set(LIB_NAME "pcl_${SUBSYS_NAME}")
 include_directories("${CMAKE_CURRENT_SOURCE_DIR}/include")
 PCL_CUDA_ADD_LIBRARY(${LIB_NAME} COMPONENT ${SUBSYS_NAME} SOURCES ${srcs} ${incs})
+target_link_libraries(${LIB_NAME} pcl_common)
 
 set(EXT_DEPS "")
 #set(EXT_DEPS CUDA)

doc/tutorials/content/building_pcl.rst

@@ -176,7 +176,6 @@ The available ROOTs you can set are as follow:
 * **CMINPACK_ROOT**: for cminpack with value `C:/Program Files/CMINPACK 1.1.13` for instance
 * **QHULL_ROOT**: for qhull with value `C:/Program Files/qhull 6.2.0.1373` for instance
 * **FLANN_ROOT**: for flann with value `C:/Program Files/flann 1.6.8` for instance
-* **EIGEN_ROOT**: for eigen with value `C:/Program Files/Eigen 3.0.0` for instance
 
 To ensure that all the dependencies were correctly found, beside the
 message you get from CMake, you can check or edit each dependency specific
@@ -253,9 +252,8 @@ then a sample value is given for reference.
 
 * Eigen
 
-+------------------+---------------------------------+---------------------------+
-| cache variable   | meaning                         | sample value              |
-+==================+=================================+===========================+ 
-| EIGEN_INCLUDE_DIR| path to eigen headers directory | /usr/local/include/eigen3 |
-+------------------+---------------------------------+---------------------------+
-
++--------------------+---------------------------------+-------------------------------+
+| cache variable     | meaning                         | sample value                  |
++====================+=================================+===============================+ 
+| Eigen3_DIR         | path to eigen cmake directory   | /usr/local/share/eigen3/cmake |
++--------------------+---------------------------------+-------------------------------+

gpu/containers/CMakeLists.txt

@@ -25,6 +25,7 @@ get_filename_component(UTILS_INC "${CMAKE_CURRENT_SOURCE_DIR}/../utils/include"
 set(LIB_NAME "pcl_${SUBSYS_NAME}")
 include_directories("${CMAKE_CURRENT_SOURCE_DIR}/include" ${UTILS_INC})
 PCL_CUDA_ADD_LIBRARY(${LIB_NAME} COMPONENT ${SUBSYS_NAME} SOURCES ${srcs} ${incs})
+target_link_libraries(${LIB_NAME} pcl_common)
 
 #Ensures that CUDA is added and the project can compile as it uses cuda calls.
 set_source_files_properties(src/device_memory.cpp PROPERTIES LANGUAGE CUDA)

io/CMakeLists.txt

@@ -1,7 +1,7 @@
 set(SUBSYS_NAME io)
 set(SUBSYS_DESC "Point cloud IO library")
 set(SUBSYS_DEPS common octree)
-set(SUBSYS_EXT_DEPS boost eigen)
+set(SUBSYS_EXT_DEPS boost eigen3)
 
 set(build TRUE)
 PCL_SUBSYS_OPTION(build "${SUBSYS_NAME}" "${SUBSYS_DESC}" ON)